Today’s share price is £22 lower than the price per share offered in a hostile takeover bid by Pfizer three years ago.

AZ, which is currently building its new headquarters in Cambridge, announced this morning that results from a trial showed that Imfinizi did not improve progression free survival in lung cancer patients compared to using chemotherapy. However, there were positive results from trials involved another AZ lung cancer treatment.

Mr Soriot, commenting on first half results, said: “Our performance in the first half was in line with expectations as we experience the loss of exclusivity of Crestor and Seroquel XR in the US.

“We continued to deliver transformative science across the pipeline, particularly in oncology. Imfinzi was launched in bladder cancer while we published practice-changing data in breast cancer for Lynparza, our first-in-class PARP inhibitor. In lung cancer, we strengthened our unique portfolio focused on both the genetic drivers of disease and immunotherapy. In the first half, we shared positive results for Imfinzi in the PACIFIC trial and reported more encouraging data for Tagrisso in patients with central nervous system metastases.

“I’m excited about our pipeline-driven transformation as we continue to deliver for shareholders on our strategy to return to sustainable long-term growth. In a pivotal year for AstraZeneca, we remain focused on realising the potential of our pipeline, growing our new launch medicines and bringing our strong science to patients.”

AstraZeneca also announced a $8.5bn global strategic co-operation deal with Merck to help commercialise one of the firm’s other cancer drugs Lynparza.

In its half-year results AstraZeneca posted a 11pc drop in sales to $10.5bn and a 37pc increase in operating profit to $1.8bn.